import java.util.Scanner;
public class First {
	public static void main(String[] args) {
	getSJXarea();
	getZFXarea();
	getCFXarea();
	}
	public static void getSJXarea () {
	Scanner SC =new Scanner(System.in);
	System.out.println("Enter the bottom of the triangle:");
	double a = SC.nextDouble();
	System.out.println("Enter the height of the triangle:");
	double b =SC.nextDouble();
	System.out.println("The area of the triangle is:" + (a*b*0.5));
	}
	public static void getZFXarea (){
	Scanner SC =new Scanner(System.in);
	System.out.println("Enter the side length of the square:");
	double a =SC.nextDouble();
	System.out.println("The area of the square is:" + (a*a));
	}
	public static void getCFXarea(){
	Scanner SC =new Scanner(System.in);
	System.out.println("Enter the length of the rectangle:" );
	double a =SC.nextDouble();
	System.out.println("Enter the width of the rectangle:");
	double b =SC.nextDouble();
	System.out.println("The area of the rectangle is:"+(a*b));
	}
}